Automatic tuning device for radio receivers



H. A. GATES AUTOMATIC TUNING DEVICE FOR RAD-IO RECEIVERS Oct. 19, 1937.

Filed Feb. 26, 1937' INVENTOR. #0 Ward x? 6 9 12 6 BY WM 7% ORNEY.

Patented Oct. 19, 1937 p i a j UNITED T S 2,096,510 AUTOMATIC TUNING nEvrcnroammm: j-

HowardA. Gates, Detroit, H I I i c, Application February 26, muse-111m. 121,972. J. 1

50mm. (oi. nit-124.1)"; f p, (This invention relates to radio receivers and" any suitable meanst.-In.-this instance the edges v has particular reference to an automatic tuning ll of the bushing 1 I! are spunover ,the walls of v I device for such receivers. a the-member l0, andxabout-the edges of the-cen- An object of the invention is the provision, of trally disposed opening. formed. in the back ;,of

5 an automatic tuning device whichis simple in the member Ill. The bushingli is secured to the; 5 construction, inexpensive to manufacture, and housing ofithe tuning condenser byany suitabley easily attached to an ordinary radio receiving set. means which holds it against rotation. v

Another object of the invention is the provision An indicator needle l5'is.press+fitted onto the of anautomatic tuning device for radio receivers shaft 1 and is arranged torot'ate withsaid shaft.

which is extremely accurate in its functioning Positioned in front of the needle i5 is an annular; 10 after it isonce set. a member lithe, purpose offwhich is explained Another object of the invention is the provision hereinafter. I The member I6 has its edges-rolled of a device of the character referred to which as at la in order to reinforce it and to give. it a. may be readily attached and adjusted for autofinished appearance. JA retaining element I9 is matic tuning by a layman without the necessity arranged to engage the inner. periphery of the side 515 V of using special tools or equipment.- walls of the member". Themembe'rli is-uti- 1 Another object of the invention is the provilizedforthe purpose of supporting the ,stylus,.;as.,.

sion of a device of the character referred to which hereinafter explained, and. is connected to the i may be used'to automatically tune in the'maxi cover-plate which'in this instanceis illustrated 20' mum number of stationson a radio receiver. as -being made of glass although it. may be made 20 1 A further object of the invention is to generally of any transparent material, to permit the dial -9 improve tuning devices for radio receivers by the to be seen at all times; .The glass cover-plate 20 provision of mechanical means for accurately logis held in the annular member I6 by means of the,

V ging stations for an individual radio set and meretainingv element f l9. It'ris shock insulatedby chanical' means for re-locating said stations means of a cork gaskets, which is positioned 25 after the same have been logged. between the back of. the glass =20 and an offset I The foregoing and other advantages and obformed in the side wall o1v the member its-The jects will appear asthe description proceeds, refmember is adapted torotatewith the shaftll erence being made to the drawing, in which: of the tuning, condenser. The rotation-is made Fig. 1 isa fragmentary front elevation, with possible by'reason of the'fact'that the glasscover-nall,

parts broken away, illustrating my device'as plate "is connected to the: shaft] by;means being attached to a conventional radio receiver. hereinafterdescribed.' It will be understood that Fig. 2 is a. section taken on line 22 of Fig.1. the cover-plate 10 is provided with a centrally Fig. 3 is a front elevation, with parts broken disposed opening into which is fitted a small dishaway, of the rotatable member carrying the shaped stamping 22', which has aflared rim.23. 5

stylus. v A backing washer-24 is secured to: the stamping Referring now more particularly to the' draw 22 by means of rivetsv 25, and :the glass cover-;' ing; it will be seen that I'have illustrated-my inplate 20 is shockinsulatedon either side by means vention in position on a conventional radio reof cork or felt washers. This assembly is then 40 ceiver, wherein 5 indicates the cabinet and 6 (Fig. secured to the shaft "I' by means .of'thebolt-'2'|,

2) represents the plates of a tuning condenser. which is insertedin an'internally threaded bore The principal elements of my invention are 28 positioned in the'shaft I. arranged to be supported upon the shaft 1', and At a predetermined place on .the. edge of the the body of the tuning condenser, and thefront member l6, Ihave caused to be formedfan offset wall 8 of the cabinet5, in the manner described 29, the latter having its edges iinturned for re-- 45 more particularly hereinafter. I inforcingfi'The offset 29 is provided with a The conventional dial 9 (Fig. 2) of the radio centrally disposed opening 30 into whichflis inreceiver is supported in a dish-shaped stamping serted, and securedby spinning or other suitable ID, the edges of which are rolled as at l I to form means, a small bushingil. Atsecond bushing 32 a retaining rim. A spring wire retaining element extends longitudinally through the bushing '3l 9 L I2 is positioned in front of the dial 9, and pre and is-free to slide thereincq Superimposed, on vents the latter'from being displaced from the the bushing 32"is1a1hollow/knob. the latter rim l I of the member ID. The dial supporting being arranged to cover thebushing 3| and the member I0 is held in position about the shaft I spring 33, which is held between the offset 29 by means of abushing l3 to which it is secured by and a corresponding offset formed in the inner end and riveting at the other.

wall of the hollow knob ll. A pointed pin 3!, which serves as a stylus as hereinafter described, extends through the bushings 3| and 32, and the hollow knob 34, and is secured against displacement by means of an enlarged shoulder at one For the sake of brevity I will refer to this last described assembly as the stylus.

. Secured to the front wall 8 of the cabinet 5 by means of small screws 36 is an'escutcheon plate 31, which is primarily an annular member having a cross-section as illustrated in Fig. .2. This g dial 9. with this device an amateur can mark annular member 31, which I will refer to hereinafter as the escutcheonp'late, is-preferably made of a soft material such as gilders metal or other comparatively softmetal which will take a polish or finish. The escutcheon plate 31 is arranged to carry the call letters of radio broadcasting stations as indicated by the character 38, Fig. 1. The call letters may be placed on the escutcheon plates! byiany suitable means and are positioned on the escutcheon .plate 31 in such manner as to :registerwithcorresponding wave length or kilocycl'e calibrations, as indicated by the reference numeral 3!,carried on the indicator dial 9. -=In the disclosureherein made the dial 9 carries long wave lengths along the top, and

short wave lengths along the bottom. The reference character 40 indicates. the volume and 'othercontrols on the receiver, but these have no relation to thevinvention, exceptthrough theirordinary functions in connection with, a radio receiving set. 4

i The purpose of the mechanism just described is to enable the user to permanently designate the predetermined positions of given stations on, the

escutcheon plate, so that it is .a comparatively easy matter to again tune the setto a particular broadcastingstation after a setting is once made. It is possiblewith thisdevice to. indicate on theescutcheon plate almost-as many stations as it is possible to register on the dial ,9 of the receiving set.

..-.1 -The operation of the devicejisverysimple. After itis assembled and in .position on a radio receiving. set, and it is desired to fix the tuning position thereon of any given broadcasting station,

the following operations are carried out- The operator simply takes hold of the knob '34 and rotates the same about the axis I until the-needle or pointer l5, indicates the desired tuning position of a certain station on the dial 9,:

for it will be remembered-that the needle or 'poin'ter lSand the member. iii are fixed to and adapted to rotate with the tuning condenser shaft 1'. When the most-'eflicient tuning position for a given station is reached; the operatorthenv marks i that position on the. escutcheon plate 31 by means of the stylus". To do this itis only necessary to move the stylus 35 toward the escutcheon plate, and whendn. contact with the latter, the stylus 35 is struck with sufllcientforcewith the hand or any instrument, so that the pointof the stylus makes an indentation at the desired location on the escutcheon plate. The spring, tends to return thestylus 35 to its inoperative position. The corresponding letters of the broadcasting stationv in tune are then positioned on the escutcheon plate immediately opposite the indentae tion made thereon withthe stylus. The proper tuning position .of any desired station, whether of short or long wave length, may then be indicated escutcheon plate. t v p i 3. In combination with a radio receiver hav-e in the same manner, and when it is desired to retune the set to any predetermined station so marked it is a simple matter to rotate the stylus to the approximate position of the station, and then obtain an absolutely accurate re-tuning by means of feeling the point of thestylus into the respective indentation for that station theretofore made.

Because of the infinitesimal amount of room taken by the indentations on the escutcheon plate,

it is possible to mark the plate for as many tuning positions as it is possible to indicate on the contact said escutcheon plate, and atransparent cover memberfor said dial secured toj'saidTro-f tatable member.

2. In combination with a radio receiver having a dial and a revolving needle, an escutcheon plate adjacent said dial consisting 'of comparatively, soft material, a membersynchronizedfor rotation with said needle, said member having a stylus thereon made of comparatively hard material, said stylus being slidably and resiliently m'ount-' ed in-said memberand adapted to be struckto form indentations-at desired positions on said ing a fixed dial anda needle arranged to revolve adjacent said dial, an escutcheon plate adjacent said dial, a. member synchronized 'forfrotation with said needle,said memberlhaving a transparent irontsection through which said dial and said needle are visibleat alltirnes, and'astylus slidably secured to said member'and arranged so that it may be struck to [form indentations on said escutcheon plate at predetermined positions indicated by saidneedle.

4. In combinationwith afradio receiver having-a tuning condenser includingmeans for indicating various positions of said tuning cons denser, an escutcheon plate adjacent said'tuning" condenser, a member arranged to synchronously rotate with the shaft-of said tuning condenser, said member having a transparent section through which said indicating means are at all times visible and a stylus slidably secured to said member} and arranged to contact saidescutcheon plate.. l

5. In combination with a .radio receiver hav ing a tuning condenser and means for indicating the'various positions of .said condenser, an annular escutcheon plate surrounding said. indi catingmeans, a member mounted for. synchronous rotation withthe shaft of said tuning condenser, a circular transparent element conce'nis-ically-rmounted on said member, an annular member secured to said transparent member and a stylus secured to said annular member and arranged to contact said escutcheon plate.

. nowaan A. GATESJ' 

